NetBSD-5.0.2/sys/arch/sparc/sparc/syscall.c
/* $NetBSD: syscall.c,v 1.21 2008/10/21 12:16:59 ad Exp $ */
/*
* Copyright (c) 1996
* The President and Fellows of Harvard College. All rights reserved.
* Copyright (c) 1992, 1993
* The Regents of the University of California. All rights reserved.
*
* This software was developed by the Computer Systems Engineering group
* at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
* contributed to Berkeley.
*
* All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Lawrence Berkeley Laboratory.
* This product includes software developed by Harvard University.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* This product includes software developed by Harvard University.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)trap.c 8.4 (Berkeley) 9/23/93
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: syscall.c,v 1.21 2008/10/21 12:16:59 ad Exp $");
#include "opt_sparc_arch.h"
#include "opt_multiprocessor.h"
#include "opt_sa.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <sys/signal.h>
#include <sys/sa.h>
#include <sys/savar.h>
#include <sys/syscall.h>
#include <sys/syscallvar.h>
#include <sys/ktrace.h>
#include <uvm/uvm_extern.h>
#include <sparc/sparc/asm.h>
#include <machine/cpu.h>
#include <machine/ctlreg.h>
#include <machine/trap.h>
#include <machine/instr.h>
#include <machine/pmap.h>
#include <machine/userret.h>
#ifdef DDB
#include <machine/db_machdep.h>
#else
#include <machine/frame.h>
#endif
#include <sparc/fpu/fpu_extern.h>
#include <sparc/sparc/memreg.h>
#include <sparc/sparc/cpuvar.h>
#define MAXARGS 8
union args {
uint64_t aligned;
register_t i[MAXARGS];
};
union rval {
uint64_t aligned;
register_t o[2];
};
static inline int handle_new(struct trapframe *, register_t *);
static inline int getargs(struct proc *p, struct trapframe *,
register_t *, const struct sysent **, union args *);
#ifdef FPU_DEBUG
static inline void save_fpu(struct trapframe *);
#endif
void syscall_plain(register_t, struct trapframe *, register_t);
void syscall_fancy(register_t, struct trapframe *, register_t);
static inline int
handle_new(struct trapframe *tf, register_t *code)
{
int new = *code & (SYSCALL_G7RFLAG | SYSCALL_G2RFLAG);
*code &= ~(SYSCALL_G7RFLAG | SYSCALL_G2RFLAG);
return new;
}
/*
* The first six system call arguments are in the six %o registers.
* Any arguments beyond that are in the `argument extension' area
* of the user's stack frame (see <machine/frame.h>).
*
* Check for ``special'' codes that alter this, namely syscall and
* __syscall. The latter takes a quad syscall number, so that other
* arguments are at their natural alignments. Adjust the number
* of ``easy'' arguments as appropriate; we will copy the hard
* ones later as needed.
*/
static inline int
getargs(struct proc *p, struct trapframe *tf, register_t *code,
const struct sysent **callp, union args *args)
{
int *ap = &tf->tf_out[0];
int error, i, nap = 6;
*callp = p->p_emul->e_sysent;
switch (*code) {
case SYS_syscall:
*code = *ap++;
nap--;
break;
case SYS___syscall:
if (!(p->p_emul->e_flags & EMUL_HAS_SYS___syscall))
break;
*code = ap[_QUAD_LOWWORD];
ap += 2;
nap -= 2;
break;
}
if (*code < 0 || *code >= p->p_emul->e_nsysent)
return ENOSYS;
*callp += *code;
i = (*callp)->sy_argsize / sizeof(register_t);
if (__predict_false(i > nap)) { /* usually false */
void *off = (char *)tf->tf_out[6] +
offsetof(struct frame, fr_argx);
#ifdef DIAGNOSTIC
KASSERT(i <= MAXARGS);
#endif
error = copyin(off, &args->i[nap], (i - nap) * sizeof(*ap));
if (error)
return error;
i = nap;
}
copywords(ap, args->i, i * sizeof(*ap));
return 0;
}
#ifdef FPU_DEBUG
static inline void
save_fpu(struct trapframe *tf)
{
struct lwp *l = curlwp;
if ((tf->tf_psr & PSR_EF) != 0) {
if (cpuinfo.fplwp != l)
panic("FPU enabled but wrong proc (3) [l=%p, fwlp=%p]",
l, cpuinfo.fplwp);
savefpstate(l->l_md.md_fpstate);
l->l_md.md_fpu = NULL;
cpuinfo.fplwp = NULL;
tf->tf_psr &= ~PSR_EF;
setpsr(getpsr() & ~PSR_EF);
}
}
#endif
void
syscall_intern(struct proc *p)
{
if (trace_is_enabled(p))
p->p_md.md_syscall = syscall_fancy;
else
p->p_md.md_syscall = syscall_plain;
}
/*
* System calls. `pc' is just a copy of tf->tf_pc.
*
* Note that the things labelled `out' registers in the trapframe were the
* `in' registers within the syscall trap code (because of the automatic
* `save' effect of each trap). They are, however, the %o registers of the
* thing that made the system call, and are named that way here.
*/
void
syscall_plain(register_t code, struct trapframe *tf, register_t pc)
{
const struct sysent *callp;
struct proc *p;
struct lwp *l;
int error, new;
union args args;
union rval rval;
register_t i;
u_quad_t sticks;
uvmexp.syscalls++; /* XXXSMP */
l = curlwp;
p = l->l_proc;
LWP_CACHE_CREDS(l, p);
sticks = p->p_sticks;
l->l_md.md_tf = tf;
#ifdef FPU_DEBUG
save_fpu(tf);
#endif
new = handle_new(tf, &code);
if ((error = getargs(p, tf, &code, &callp, &args)) != 0)
goto bad;
rval.o[0] = 0;
rval.o[1] = tf->tf_out[1];
#ifdef KERN_SA
if (__predict_false((l->l_savp)
&& (l->l_savp->savp_pflags & SAVP_FLAG_DELIVERING)))
l->l_savp->savp_pflags &= ~SAVP_FLAG_DELIVERING;
#endif
error = sy_call(callp, l, &args, rval.o);
switch (error) {
case 0:
/* Note: fork() does not return here in the child */
tf->tf_out[0] = rval.o[0];
tf->tf_out[1] = rval.o[1];
if (new) {
/* jmp %g2 (or %g7, deprecated) on success */
i = tf->tf_global[new & SYSCALL_G2RFLAG ? 2 : 7];
if (i & 3) {
error = EINVAL;
goto bad;
}
} else {
/* old system call convention: clear C on success */
tf->tf_psr &= ~PSR_C; /* success */
i = tf->tf_npc;
}
tf->tf_pc = i;
tf->tf_npc = i + 4;
break;
case ERESTART:
case EJUSTRETURN:
/* nothing to do */
break;
default:
bad:
if (p->p_emul->e_errno)
error = p->p_emul->e_errno[error];
tf->tf_out[0] = error;
tf->tf_psr |= PSR_C; /* fail */
i = tf->tf_npc;
tf->tf_pc = i;
tf->tf_npc = i + 4;
break;
}
userret(l, pc, sticks);
share_fpu(l, tf);
}
void
syscall_fancy(register_t code, struct trapframe *tf, register_t pc)
{
const struct sysent *callp;
struct proc *p;
struct lwp *l;
int error, new;
union args args;
union rval rval;
register_t i;
u_quad_t sticks;
uvmexp.syscalls++; /* XXXSMP */
l = curlwp;
p = l->l_proc;
LWP_CACHE_CREDS(l, p);
sticks = p->p_sticks;
l->l_md.md_tf = tf;
#ifdef FPU_DEBUG
save_fpu(tf);
#endif
new = handle_new(tf, &code);
if ((error = getargs(p, tf, &code, &callp, &args)) != 0)
goto bad;
if ((error = trace_enter(code, args.i, callp->sy_narg)) != 0)
goto out;
rval.o[0] = 0;
rval.o[1] = tf->tf_out[1];
#ifdef KERN_SA
if (__predict_false((l->l_savp)
&& (l->l_savp->savp_pflags & SAVP_FLAG_DELIVERING)))
l->l_savp->savp_pflags &= ~SAVP_FLAG_DELIVERING;
#endif
error = sy_call(callp, l, &args, rval.o);
out:
switch (error) {
case 0:
/* Note: fork() does not return here in the child */
tf->tf_out[0] = rval.o[0];
tf->tf_out[1] = rval.o[1];
if (new) {
/* jmp %g2 (or %g7, deprecated) on success */
i = tf->tf_global[new & SYSCALL_G2RFLAG ? 2 : 7];
if (i & 3) {
error = EINVAL;
goto bad;
}
} else {
/* old system call convention: clear C on success */
tf->tf_psr &= ~PSR_C; /* success */
i = tf->tf_npc;
}
tf->tf_pc = i;
tf->tf_npc = i + 4;
break;
case ERESTART:
case EJUSTRETURN:
/* nothing to do */
break;
default:
bad:
if (p->p_emul->e_errno)
error = p->p_emul->e_errno[error];
tf->tf_out[0] = error;
tf->tf_psr |= PSR_C; /* fail */
i = tf->tf_npc;
tf->tf_pc = i;
tf->tf_npc = i + 4;
break;
}
trace_exit(code, rval.o, error);
userret(l, pc, sticks);
share_fpu(l, tf);
}
/*
* Process the tail end of a fork() for the child.
*/
void
child_return(void *arg)
{
struct lwp *l = arg;
/*
* Return values in the frame set by cpu_fork().
*/
userret(l, l->l_md.md_tf->tf_pc, 0);
ktrsysret((l->l_proc->p_lflag & PL_PPWAIT) ? SYS_vfork : SYS_fork,
0, 0);
}